The present invention relates to charging systems for electric vehicles and more particularly to charging system that provide improved alignment between the primary coil and the secondary coil.
Inductive power is used in a variety of vehicle charging applications. These systems include a primary charging coil connected to a power source and a secondary coil within the vehicle connected to a battery. Power is applied to the primary charging coil, which induces a current in the secondary coil to charge the battery. Inductive charging systems can experience efficiency issues if 1) the primary coil and secondary coil are not adequately aligned with one another and/or 2) the coils are not sufficiently proximate one another. Prior art designs include a variety of techniques for aligning the coils and/or moving the coils into physical proximity. Unfortunately, those designs are relatively complex and often include relatively delicate sensing and movement systems, which may require calibration and maintenance over time. Further, an animal or other moving object may wander between the primary and secondary coils, which may interfere with the efficiency of the coupling between the primary and secondary coil.